No-voltage release mechanism.



AP YLICATION FILED M LK- 18, 1912.

Patentd Nov. 12, 1912.

Jaucfnfor LUMBIA PLANoulAPM Cm, WASHINGTON D c UNITED PATENT OFFICE.

AUSTIN KIMBLE, OF CHICAGO, ILLINOIS, ASSIGNOR TO KIMBLE ELECTRIC COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

Specification of Letters Patent.

Patented Nov. 12, 1912.

Application filed March 18, 1912. SeriaINo. 684,650.

T 0 all whom it may concern:

Be it known that I, AUs'rIN KIMBLE, a citizen of the United States of America, and a resident of Chicago, county of Cook, State of Illinois, have invented certain new and useful Improvements in No-Voltage Release Mechanism, of which the following is a specification.

The main objects of this invention are to provide a simple and improved form of novoltage release mechanism particularly adapted for use in connection with controllers, switches, rheostats, and similar electrical devices for use wherein it isdesirable to automatically shut off the current when the voltage falls below a certain predetermined minimum; and to provide a construction of this kind in which the usual destructive wear, and the consequent frequent renewal of parts is avoided.

An illustrative embodiment of this invention is shown in the accompanying drawings, in which Figure l is a face view of an electric controller provided with a no-voltage release mechanism designed according to this invention for alternating currents. Fig. 2 is a detail showing in elevation the relationship of the sectors which control the holding or release of the movable controller element. Fig. 3 is a sectional detail taken on the line A A of Fig. 1. Fig. 41 is a sectional detail of the solenoid forming part of the release mechanism.

The controller may be of any usual form to suit the service for which it is intended, and in the form shown in the drawings it comprises two annular sets of stationary contact members 1, and a controller lever 2 pivoted at 3 and carrying a pair of springpressed contact brushes or shoes 4 of ordinary construct-ion. The lever 2 is normally urged toward its oil position by means of a helical spring 5 (Fig. 3) coiled around the pivot stud 3 and having its ends respectively connected to the lever 2 and the front plate 6 of the controller.

Arranged concentrically to the path of the lever 2 is a sector-shaped rack or stop member 7 provided with a series of stop shoulders 8 spaced apart to correspond with the angular spacing of the contacts 1. The member 7 is secured to the face plate 6 by means of screws 9 passing through slotted feet 10, and the slots 11 are arc-shaped and concentric with the pivot 3 and of such length as to permit a shifting of the member 7 to an angular extent equal to one half the interval between adjacent contacts 1.

Arranged concentrically with respect to the member 7 is a second arc-shaped member 12, which for the purpose of distinguishing it from the member 7 will be herein called a guard member. This guard member 12 is provided with a series of indentations 13 corresponding in location to the recesses 14 at the sides of the shoulders 8. These indentations 13 are wedge-shaped so that the sides thereof which are nearest to the off position of the controller lever are inclined as shown in Fig. 2. The upper surfaces 15 and 16 of the members 7 and 12 respectively are flush with each other, and are of such relative extent that the holding pawl or detent 17 of the controller lever will be free to engage the shoulders 8 when the member 7 is at the limit of its move ment toward the right of Fig. 1, but will be prevented from such engagement by the overlapping of the surfaces 15 and 16 when the members 7 and 12 are in the relative positions in which they are shown in Figs. 1 and 2.

In the form shown, the detent 17 is pivoted at 18 on the controller lever 2, and is provided with an arm 19 connected with a push rod 20 extending through the handle 21 of the lever and normally urged upwardly by a spring 22 to force the detent 17 into engagement with the stop shoulders 8. To release the detent 17 manually the head 23 on the rod 20 may be depressed by the operators thumb as he grips the handle 21. It will be noticed from Fig. 1 that when the members 7 and 12 are in the position shown in Fig. 2 the shoulders 24 at the right-hand side of the recesses 14 in the member 7 are slightly at the right of the crests of the inclined surfaces 25 of the respective recesses 13, so that in swinging the lever to the right the detent 17 may be caused to engage any one of the shoulders 24 to shift the member 7 toward the right-hand limit of its movement.

A locking pawl or detent 26 is pivoted at 27 on the face plate 6 in position to engage a shoulder 28 on the member 7, and thereby lock said member at the right-hand limit of its movement. The pawl 26 is normally urged by gravity into its position for engaging the shoulder 28, and has a. tail 29 extending into the path of the stem 30 of the renewal of the rack member.

armature 31 of a solenoid 32, the solenoid being so mounted that the weight of its armature will normally release the pawl 26 except when current is on, at which time the armature 31 will be lifted clear of the tail 29 of pawl 26. The circuit connections are not shown in the drawings or herein described in detail since it is obvious that any method of connection may be employed so long as the solenoid is so arranged as to be energized when the current is on and deenen gized when the current is off.

The operation of the device shown is as follows: To shift the lever 2 toward the right of Fig. 1 the operator grasps the handle 21 and depresses the head 23 with his thumb. This retracts the detent 17 and allows him to shift the lever directly to any position. is the lever 2 approaches the po sition to which it to be set the operator releases the head 23 and the final movement of the lever toward the right causes the detent 17 to engage the adjacent shoulder 24 and shift the member 7 to the limit of its move ment. At this time the recesses 14 will register with the deepest portions of the recesses 13, and the detent 17 will, therefore, become seated in a holding position behind theshoulder 8. The movement of the member 7 toward the right will have shifted the shoulder 28 clear of the end of the pawl 26, and said pawl will drop behind the shoulder 28 and look the member 7 As the current is on as soon as the lever 2 has moved to the right of the 01f contact button, or when the main switch is closed optional, the solenoid will have become energized and will lift its armature and thereby allow the pawl 26 to become seated behind the shoulder 28. As the pawl 26 and shoulder 28 lock the member '7, the shoulder 8, which is in engagement with the detent 1'7, will lock the lever If for any reason, such as the breaking of the circuit, there is a drop in the voltage of the energizing current of the solenoid 32, the armature 31 will be released and will fall causing the arm 30 to strike a hammer blow upon tail 29, and retract the pawl 26 so as to release the member 7 The spring 5 will thereupon swing the lever 2 toward the left and carry with it the memher 7 through the pressure of the detent 17 against the respective shoulder 8, but during such movement the inclined shoulder 25 will lift the detent clear of the shoulder 8 and allow it to ride on the overlapping surfaces 15 and 16 so as to permit the lever 2 to be swung by the spring 5 to its oflf position. As the member 7 is free to move with the detent while the latter is being retracted there is no wear whatsoever on the shoulders 8 during the act of releasing the lever, and, therefore, said shoulders will wear indefinitely, and will not necessitate the frequent Such wear and necessity for renewal are serious faults of the ordinary forms of no-voltage release mechanisms.

Although but one specific embodiment of this invent-ion has been herein shown and described, it will be understood that numerous details of the construction shown may be altered or omitted without departing from the spirit of this invention as defined by the following claims.

I claim 1. In a device of the class described, the combination of a pair of controller mem bers, one being movable relatively to the other, means providing a series of stop shoulders adjacent to one of said members, a detent coacting with said stop shoulders for securing said members in different relative positions, and a guard member extending along said series of shoulders and having registering recesses, said guard member and series of shoulders being relatively movable and being adapted in one position to prevent engagement of said detent with said shoulders and in another position to permit such engagement.

2. In a device of the class described, the combination of a movable controller element, a detent carried thereby, a rack member adapted to coact with said detent for securing said movable member in different positions, a guard member having guide surfaces and depressions corresponding in location with those on said rack member and respectively adapted to prevent said detent from engaging the shoulders on said rack member when said rack and guard membe "s are in one position relative to each other and to permit such engagement when they are in another relative position, and means for automatically shifting one of said guard and rack members relative to the other.

In a device of the class described, the combination of a movable controller element, a detent carried thereby, a racl: member adapted to coact with said detent for securing said movable member in different positions, a guard member having guide surfaces and depressions corresponding in location with those on said rack member and respectively adapted to prevent said detent from engaging the shoulders on said rack member when said rack and guard members are in one position relative t5 each other and to permit such engagement when they are in another relative position, and electrically controlled means for automatically shifting one of said guard and rack members relative to the other.

4:. In a controller. the t'mulunfum f a rotatable controller element, a springpressed detent carried thereby, a rack sector located to coact With said detent for holding said controller element in different positions, a guard sector located adjacent to said rack sector and having registering recess for receiving said detent, a dog adapted to hold said movable rack sector in position to register with said guard sector, electro-inagnetic means adapted to hold said dog in its engaged position and to release said dog under respectively different current conditions, and a spring normally urging said controller member toward its ofl" position.

5. In a device of the class described, the combination of a stationary controller element a rotary controller element, a spring normally urging said rotary element toward its ofl position, means providing a shoulder for holding said controller element in a predetermined position away from its off position and being movable toward said off position, electromagnetic means for controlling the position of said shouldered means, and means providing an inclined surface having fixed relation to said stationary element and adapted through the shifting of said shouldered means to release said detent therefrom.

6. In a controller, the combination of a series of contacts, a rotary controller element having acont-act located to successively engage the contacts of said series, a movable detent on said rotary controller element, a rack sector having a series of shoulders adapted to engage said detent for holding said rotary controller element in different positions, said rack sector being shiftable toward the off position of said rotary controller element, electro-magnetically controlled means for preventing such shifting, and means positioned to coact with said detent for releasing the same from said stop shoulders through the movement of said rack sector.

Signed at Chicago this 15th day of March 1912.

AUSTIN KIMBLE. Witnesses:

EUGENE A. RUMMLER, EDWIN PHELPS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C. 

